The environment committee of southern Belgium’s Walloon Parliament voted unanimously for the ban, which will take effect on 1 September, 2019.
Both Jewish kosher and Islamic halal rituals require the butcher to swiftly slaughter the animal by slitting its throat and draining its blood, a process condemned by animal rights campaigners, who argue it is more humane to stun animals before killing them.
Similar legislation has been proposed by the parliament in the northern Flemish region.
The European Jewish Congress has strongly condemned the decision, calling it “scandalous”.
“This decision, in the heart of Western Europe and the centre of the European Union, sends a terrible message to Jewish communities throughout our continent that Jews are unwanted,” EJC president Moshe Kantor said.
“It attacks the very core of our culture and religious practice and our status as equal citizens with equal rights in a democratic society. It gives succour to antisemites and to those intolerant of other communities and faiths.”
He added: “We call on legislators to step back from the brink of the greatest assault on Jewish religious rights in Belgium since the Nazi occupation of the country in World War II.”
Belgium’s Muslim community said its religious council has previously expressed its opposition to stunned slaughter and there had been no change in its stance since then.
“Muslims are worried about whether they can eat halal food … in conformity with their religious rites and beliefs,” the Belgian Muslim Executive said.
Countries including Denmark, Switzerland and New Zealand already prohibit unstunned slaughter.